Tanks may be designed in many different configurations, such as spheres, cylinders, cones and shells in general, as well as prismatic shapes. The principal advantage of prismatic shapes is that they nest closer to each other, minimising the volume taken up by such tanks.
Such tanks may be supported by timber of various types or similar materials. The present technology for anchoring such supports to the bottom of the tank is to weld on guide rails. For certain materials welds have considerably lower strength then the base metal which prevents full utilisation of the base metal. Welds are also more susceptible to fatigue. To avoid initiating cracks propagating from welds and propagating through the thickness of the shell the design is such that there are no welds in the webs of the H-beams making up the panels.
U.S. Pat. No. 5,531,178 discloses a support structure for LNG tanks. The bottom supports are restrained by guide rails. No description of how these guide rails are fastened to the bottom of the tank is provided.
WO 2008/133785 discloses a tank for transportation of LNG. The supports between the bottom of the tank and the floor of the ship hull are only described as “support chocks”, and there is no mention of how, or if, the supports are anchored to the tank.